cm-n.cz

Valid Email Server

Domain Overview

DNS: ✓ 1d ago Checker: ✓ 1d ago
cm-n.cz
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]

Checked via [email protected] · 2026-05-20 20:47:26 UTC · ↺ Refresh

MX Hostnames

  • cmn-cz0e.mail.protection.outlook.com

MX Priorities

  • cmn-cz0e.mail.protection.outlook.com: 10

A / AAAA Records

  • 20.8.217.220 (no PTR)

Mail Server IPs

  • 52.101.68.15 ↩ mail-db6pr03cu00107.inbound.protection.outlook.com
  • 52.101.73.19 ↩ mail-as8pr04cu00803.inbound.protection.outlook.com
  • 52.101.68.27 ↩ mail-db7pr03cu00503.inbound.protection.outlook.com
  • 52.101.73.153 ↩ mail-as8pr05cu00401.inbound.protection.outlook.com
  • 2a01:111:f403:ca04::6 ↩ mail-db4pr02cu00406.inbound.protection.outlook.com
  • 2a01:111:f403:ca09::4 ↩ mail-am0pr04cu00504.inbound.protection.outlook.com
  • 2a01:111:f403:ca09::b ↩ mail-am7pr05cu00103.inbound.protection.outlook.com
  • 2a01:111:f403:ca04::c ↩ mail-db9pr02cu00204.inbound.protection.outlook.com

SOA Record

Raw SOA ns1.websupport.cz admin.websupport.cz 1779279957 7200 2048 1048576 2560
Primary NS (mname)
ns1.websupport.cz
Admin Email (rname)
admin@websupport.cz
Serial
1779279957
Refresh
7200s
Retry
2048s
Expire
1048576s
Minimum TTL
2560s

Nameservers (NS)

ns2.websupport.cz
ns3.websupport.eu
ns1.websupport.cz

SPF Record

✓ Strict (-all)
v=spf1 include:servers.mcsv.net include:spf.protection.outlook.com include:spfinc.arakis.cz include:spfi.mkii.net include:eu.mailgun.org include:spf.mailjet.com -all
📊 DNS lookups: 6/10
✓ Hard fail (-all) — strict enforcement

DMARC Record

~ Quarantine
v=DMARC1; p=quarantine; pct=100; adkim=s; aspf=s
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Strict · DKIM alignment: Strict
⚠ No aggregate reports (rua= not set)

DKIM Selectors

✓ 1 found
k1._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: k1

Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses

All TXT Records

7 records
  • SPFv=spf1 include:servers.mcsv.net include:spf.protection.outlook.com include:spfinc.arakis.cz include:spfi.mkii.net include:eu.mailgun.org include:spf.mailjet.com -all
  • k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCovuQin1NMH/v2QTL1Nbqif8OHhRT7zCGH0F22vOFh/1nBwxTuElZB1lgYj7Eypz0NbkJuYNhT82CoZT2DhzACZuxFJnZAjQ8USrSs32VnQ3ib17EHg0kVX/8ZAhXt81u+ZxXNKMN4CWLDS4L95l2jFB9VysACJt6gtYsTBaDb7QIDAQAB
  • MS=ms78680979
  • apple-domain-verification=e8JB6xpcFBhPoJSH
  • have-i-been-pwned-verification=26dc9d244d1b1217b695c548524d818e
  • google-site-verification=VSNy2H_wcl3qoYi8raY5q_EtprajT1F1jWWSqzcARwQ
  • google-site-verification=ei929noBZ6IRR9r_MTvaKrUXcT6p9uZYS-0HGqJyChU
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